1 /*
2  * Copyright (c) 2018, 2019 Ori Bernstein <ori@openbsd.org>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include <sys/types.h>
18 #include <sys/stat.h>
19 #include <sys/queue.h>
20 #include <sys/uio.h>
21 #include <sys/socket.h>
22 #include <sys/wait.h>
23 #include <sys/syslimits.h>
24 #include <sys/resource.h>
25 #include <sys/socket.h>
26 
27 #include <errno.h>
28 #include <err.h>
29 #include <fcntl.h>
30 #include <stdio.h>
31 #include <stdlib.h>
32 #include <string.h>
33 #include <stdint.h>
34 #include <sha1.h>
35 #include <zlib.h>
36 #include <ctype.h>
37 #include <limits.h>
38 #include <imsg.h>
39 #include <time.h>
40 #include <uuid.h>
41 #include <netdb.h>
42 #include <netinet/in.h>
43 
44 #include "got_error.h"
45 #include "got_reference.h"
46 #include "got_repository.h"
47 #include "got_path.h"
48 #include "got_cancel.h"
49 #include "got_worktree.h"
50 #include "got_object.h"
51 #include "got_opentemp.h"
52 #include "got_fetch.h"
53 
54 #include "got_lib_delta.h"
55 #include "got_lib_inflate.h"
56 #include "got_lib_object.h"
57 #include "got_lib_object_parse.h"
58 #include "got_lib_object_create.h"
59 #include "got_lib_pack.h"
60 #include "got_lib_sha1.h"
61 #include "got_lib_privsep.h"
62 #include "got_lib_object_cache.h"
63 #include "got_lib_repository.h"
64 
65 #ifndef nitems
66 #define nitems(_a)	(sizeof((_a)) / sizeof((_a)[0]))
67 #endif
68 
69 #ifndef MIN
70 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
71 #endif
72 
73 static int
74 hassuffix(char *base, char *suf)
75 {
76 	int nb, ns;
77 
78 	nb = strlen(base);
79 	ns = strlen(suf);
80 	if (ns <= nb && strcmp(base + (nb - ns), suf) == 0)
81 		return 1;
82 	return 0;
83 }
84 
85 static const struct got_error *
86 dial_ssh(pid_t *fetchpid, int *fetchfd, const char *host, const char *port,
87     const char *path, const char *direction, int verbosity)
88 {
89 	const struct got_error *error = NULL;
90 	int pid, pfd[2];
91 	char cmd[64];
92 	char *argv[11];
93 	int i = 0;
94 
95 	*fetchpid = -1;
96 	*fetchfd = -1;
97 
98 	if (port == NULL)
99 		port = "22";
100 
101 	argv[0] = GOT_FETCH_PATH_SSH;
102 	argv[1] = "-p";
103 	argv[2] = (char *)port;
104 	if (verbosity == -1) {
105 		argv[3 + i++] = "-q";
106 	} else {
107 		/* ssh(1) allows up to 3 "-v" options. */
108 		for (i = 0; i < MIN(3, verbosity); i++)
109 			argv[3 + i] = "-v";
110 	}
111 	argv[3 + i] = "--";
112 	argv[4 + i] = (char *)host;
113 	argv[5 + i] = (char *)cmd;
114 	argv[6 + i] = (char *)path;
115 	argv[7 + i] = NULL;
116 
117 	if (pipe(pfd) == -1)
118 		return got_error_from_errno("pipe");
119 
120 	pid = fork();
121 	if (pid == -1) {
122 		error = got_error_from_errno("fork");
123 		close(pfd[0]);
124 		close(pfd[1]);
125 		return error;
126 	} else if (pid == 0) {
127 		int n;
128 		close(pfd[1]);
129 		dup2(pfd[0], 0);
130 		dup2(pfd[0], 1);
131 		n = snprintf(cmd, sizeof(cmd), "git-%s-pack", direction);
132 		if (n < 0 || n >= sizeof(cmd))
133 			err(1, "snprintf");
134 		if (execv(GOT_FETCH_PATH_SSH, argv) == -1)
135 			err(1, "execl");
136 		abort(); /* not reached */
137 	} else {
138 		close(pfd[0]);
139 		*fetchpid = pid;
140 		*fetchfd = pfd[1];
141 		return NULL;
142 	}
143 }
144 
145 static const struct got_error *
146 dial_git(int *fetchfd, const char *host, const char *port, const char *path,
147     const char *direction)
148 {
149 	const struct got_error *err = NULL;
150 	struct addrinfo hints, *servinfo, *p;
151 	char *cmd = NULL, *pkt = NULL;
152 	int fd = -1, totlen, r, eaicode;
153 
154 	*fetchfd = -1;
155 
156 	if (port == NULL)
157 		port = GOT_DEFAULT_GIT_PORT_STR;
158 
159 	memset(&hints, 0, sizeof hints);
160 	hints.ai_family = AF_UNSPEC;
161 	hints.ai_socktype = SOCK_STREAM;
162 	eaicode = getaddrinfo(host, port, &hints, &servinfo);
163 	if (eaicode) {
164 		char msg[512];
165 		snprintf(msg, sizeof(msg), "%s: %s", host,
166 		    gai_strerror(eaicode));
167 		return got_error_msg(GOT_ERR_ADDRINFO, msg);
168 	}
169 
170 	for (p = servinfo; p != NULL; p = p->ai_next) {
171 		if ((fd = socket(p->ai_family, p->ai_socktype,
172 		    p->ai_protocol)) == -1)
173 			continue;
174 		if (connect(fd, p->ai_addr, p->ai_addrlen) == 0)
175 			break;
176 		err = got_error_from_errno("connect");
177 		close(fd);
178 	}
179 	if (p == NULL)
180 		goto done;
181 
182 	if (asprintf(&cmd, "git-%s-pack %s", direction, path) == -1) {
183 		err = got_error_from_errno("asprintf");
184 		goto done;
185 	}
186 	totlen = 4 + strlen(cmd) + 1 + strlen("host=") + strlen(host) + 1;
187 	if (asprintf(&pkt, "%04x%s", totlen, cmd) == -1) {
188 		err = got_error_from_errno("asprintf");
189 		goto done;
190 	}
191 	r = write(fd, pkt, strlen(pkt) + 1);
192 	if (r == -1) {
193 		err = got_error_from_errno("write");
194 		goto done;
195 	}
196 	if (asprintf(&pkt, "host=%s", host) == -1) {
197 		err = got_error_from_errno("asprintf");
198 		goto done;
199 	}
200 	r = write(fd, pkt, strlen(pkt) + 1);
201 	if (r == -1) {
202 		err = got_error_from_errno("write");
203 		goto done;
204 	}
205 done:
206 	free(cmd);
207 	free(pkt);
208 	if (err) {
209 		if (fd != -1)
210 			close(fd);
211 	} else
212 		*fetchfd = fd;
213 	return err;
214 }
215 
216 const struct got_error *
217 got_fetch_connect(pid_t *fetchpid, int *fetchfd, const char *proto,
218     const char *host, const char *port, const char *server_path, int verbosity)
219 {
220 	const struct got_error *err = NULL;
221 
222 	*fetchpid = -1;
223 	*fetchfd = -1;
224 
225 	if (strcmp(proto, "ssh") == 0 || strcmp(proto, "git+ssh") == 0)
226 		err = dial_ssh(fetchpid, fetchfd, host, port, server_path,
227 		    "upload", verbosity);
228 	else if (strcmp(proto, "git") == 0)
229 		err = dial_git(fetchfd, host, port, server_path, "upload");
230 	else if (strcmp(proto, "http") == 0 || strcmp(proto, "git+http") == 0)
231 		err = got_error_path(proto, GOT_ERR_NOT_IMPL);
232 	else
233 		err = got_error_path(proto, GOT_ERR_BAD_PROTO);
234 	return err;
235 }
236 
237 const struct got_error *
238 got_fetch_parse_uri(char **proto, char **host, char **port,
239     char **server_path, char **repo_name, const char *uri)
240 {
241 	const struct got_error *err = NULL;
242 	char *s, *p, *q;
243 	int n;
244 
245 	*proto = *host = *port = *server_path = *repo_name = NULL;
246 
247 	p = strstr(uri, "://");
248 	if (!p) {
249 		/* Try parsing Git's "scp" style URL syntax. */
250 		*proto = strdup("ssh");
251 		if (proto == NULL) {
252 			err = got_error_from_errno("strdup");
253 			goto done;
254 		}
255 		s = (char *)uri;
256 		q = strchr(s, ':');
257 		if (q == NULL) {
258 			err = got_error(GOT_ERR_PARSE_URI);
259 			goto done;
260 		}
261 		/* No slashes allowed before first colon. */
262 		p = strchr(s, '/');
263 		if (p && q > p) {
264 			err = got_error(GOT_ERR_PARSE_URI);
265 			goto done;
266 		}
267 		*host = strndup(s, q - s);
268 		if (*host == NULL) {
269 			err = got_error_from_errno("strndup");
270 			goto done;
271 		}
272 		p = q + 1;
273 	} else {
274 		*proto = strndup(uri, p - uri);
275 		if (proto == NULL) {
276 			err = got_error_from_errno("strndup");
277 			goto done;
278 		}
279 		s = p + 3;
280 
281 		p = strstr(s, "/");
282 		if (p == NULL || strlen(p) == 1) {
283 			err = got_error(GOT_ERR_PARSE_URI);
284 			goto done;
285 		}
286 
287 		q = memchr(s, ':', p - s);
288 		if (q) {
289 			*host = strndup(s, q - s);
290 			if (*host == NULL) {
291 				err = got_error_from_errno("strndup");
292 				goto done;
293 			}
294 			*port = strndup(q + 1, p - (q + 1));
295 			if (*port == NULL) {
296 				err = got_error_from_errno("strndup");
297 				goto done;
298 			}
299 		} else {
300 			*host = strndup(s, p - s);
301 			if (*host == NULL) {
302 				err = got_error_from_errno("strndup");
303 				goto done;
304 			}
305 		}
306 	}
307 
308 	*server_path = strdup(p);
309 	if (*server_path == NULL) {
310 		err = got_error_from_errno("strdup");
311 		goto done;
312 	}
313 
314 	p = strrchr(p, '/');
315 	if (!p || strlen(p) <= 1) {
316 		err = got_error(GOT_ERR_PARSE_URI);
317 		goto done;
318 	}
319 	p++;
320 	n = strlen(p);
321 	if (n == 0) {
322 		err = got_error(GOT_ERR_PARSE_URI);
323 		goto done;
324 	}
325 	if (hassuffix(p, ".git"))
326 		n -= 4;
327 	*repo_name = strndup(p, (p + n) - p);
328 	if (*repo_name == NULL) {
329 		err = got_error_from_errno("strndup");
330 		goto done;
331 	}
332 done:
333 	if (err) {
334 		free(*proto);
335 		*proto = NULL;
336 		free(*host);
337 		*host = NULL;
338 		free(*port);
339 		*port = NULL;
340 		free(*server_path);
341 		*server_path = NULL;
342 		free(*repo_name);
343 		*repo_name = NULL;
344 	}
345 	return err;
346 }
347 
348 static const struct got_error *
349 check_pack_hash(int fd, size_t sz, uint8_t *hcomp)
350 {
351 	SHA1_CTX ctx;
352 	uint8_t hexpect[SHA1_DIGEST_LENGTH];
353 	uint8_t buf[32 * 1024];
354 	ssize_t n, r, nr;
355 
356 	if (sz < sizeof(struct got_packfile_hdr) + SHA1_DIGEST_LENGTH)
357 		return got_error_msg(GOT_ERR_BAD_PACKFILE, "short packfile");
358 
359 	n = 0;
360 	SHA1Init(&ctx);
361 	while (n < sz - 20) {
362 		nr = sizeof(buf);
363 		if (sz - n - 20 < sizeof(buf))
364 			nr = sz - n - 20;
365 		r = read(fd, buf, nr);
366 		if (r == -1)
367 			return got_error_from_errno("read");
368 		if (r != nr)
369 			return got_error_msg(GOT_ERR_BAD_PACKFILE,
370 			    "short pack file");
371 		SHA1Update(&ctx, buf, nr);
372 		n += r;
373 	}
374 	SHA1Final(hcomp, &ctx);
375 
376 	r = read(fd, hexpect, sizeof(hexpect));
377 	if (r == -1)
378 		return got_error_from_errno("read");
379 	if (r != sizeof(hexpect))
380 		return got_error_msg(GOT_ERR_BAD_PACKFILE,
381 		    "short pack file");
382 
383 	if (memcmp(hcomp, hexpect, SHA1_DIGEST_LENGTH) != 0)
384 		return got_error_msg(GOT_ERR_BAD_PACKFILE,
385 		    "packfile checksum mismatch");
386 
387 	return NULL;
388 }
389 
390 const struct got_error*
391 got_fetch_pack(struct got_object_id **pack_hash, struct got_pathlist_head *refs,
392     struct got_pathlist_head *symrefs, const char *remote_name,
393     int mirror_references, int fetch_all_branches,
394     struct got_pathlist_head *wanted_branches,
395     struct got_pathlist_head *wanted_refs, int list_refs_only, int verbosity,
396     int fetchfd, struct got_repository *repo,
397     got_fetch_progress_cb progress_cb, void *progress_arg)
398 {
399 	int imsg_fetchfds[2], imsg_idxfds[2];
400 	int packfd = -1, npackfd = -1, idxfd = -1, nidxfd = -1, nfetchfd = -1;
401 	int tmpfds[3], i;
402 	int fetchstatus, idxstatus, done = 0;
403 	const struct got_error *err;
404 	struct imsgbuf fetchibuf, idxibuf;
405 	pid_t fetchpid, idxpid;
406 	char *tmppackpath = NULL, *tmpidxpath = NULL;
407 	char *packpath = NULL, *idxpath = NULL, *id_str = NULL;
408 	const char *repo_path = NULL;
409 	struct got_pathlist_head have_refs;
410 	struct got_pathlist_entry *pe;
411 	struct got_reflist_head my_refs;
412 	struct got_reflist_entry *re;
413 	off_t packfile_size = 0;
414 	struct got_packfile_hdr pack_hdr;
415 	uint32_t nobj = 0;
416 	char *ref_prefix = NULL;
417 	size_t ref_prefixlen = 0;
418 	char *path;
419 	char *progress = NULL;
420 
421 	*pack_hash = NULL;
422 
423 	/*
424 	 * Prevent fetching of references that won't make any
425 	 * sense outside of the remote repository's context.
426 	 */
427 	TAILQ_FOREACH(pe, wanted_refs, entry) {
428 		const char *refname = pe->path;
429 		if (strncmp(refname, "refs/got/", 9) == 0 ||
430 		    strncmp(refname, "got/", 4) == 0 ||
431 		    strncmp(refname, "refs/remotes/", 13) == 0 ||
432 		    strncmp(refname, "remotes/", 8) == 0)
433 			return got_error_path(refname, GOT_ERR_FETCH_BAD_REF);
434 	}
435 
436 	if (!list_refs_only)
437 		repo_path = got_repo_get_path_git_dir(repo);
438 
439 	for (i = 0; i < nitems(tmpfds); i++)
440 		tmpfds[i] = -1;
441 
442 	TAILQ_INIT(&have_refs);
443 	SIMPLEQ_INIT(&my_refs);
444 
445 	if (!mirror_references) {
446 		if (asprintf(&ref_prefix, "refs/remotes/%s/",
447 		    remote_name) == -1)
448 			return got_error_from_errno("asprintf");
449 		ref_prefixlen = strlen(ref_prefix);
450 	}
451 
452 	if (!list_refs_only) {
453 		err = got_ref_list(&my_refs, repo, NULL,
454 		    got_ref_cmp_by_name, NULL);
455 		if (err)
456 			goto done;
457 	}
458 
459 	SIMPLEQ_FOREACH(re, &my_refs, entry) {
460 		struct got_object_id *id;
461 		const char *refname;
462 
463 		if (got_ref_is_symbolic(re->ref))
464 			continue;
465 
466 		refname = got_ref_get_name(re->ref);
467 
468 		if (mirror_references) {
469 			char *name;
470 			err = got_ref_resolve(&id, repo, re->ref);
471 			if (err)
472 				goto done;
473 			name = strdup(refname);
474 			if (name == NULL) {
475 				err = got_error_from_errno("strdup");
476 				goto done;
477 			}
478 			err = got_pathlist_append(&have_refs, name, id);
479 			if (err)
480 				goto done;
481 			continue;
482 		}
483 
484 		if (strncmp("refs/tags/", refname, 10) == 0) {
485 			char *tagname;
486 
487 			err = got_ref_resolve(&id, repo, re->ref);
488 			if (err)
489 				goto done;
490 			tagname = strdup(refname);
491 			if (tagname == NULL) {
492 				err = got_error_from_errno("strdup");
493 				goto done;
494 			}
495 			err = got_pathlist_append(&have_refs, tagname, id);
496 			if (err) {
497 				free(tagname);
498 				goto done;
499 			}
500 		}
501 
502 		if (strncmp(ref_prefix, refname, ref_prefixlen) == 0) {
503 			char *branchname;
504 
505 			err = got_ref_resolve(&id, repo, re->ref);
506 			if (err)
507 				goto done;
508 
509 			if (asprintf(&branchname, "refs/heads/%s",
510 			    refname + ref_prefixlen) == -1) {
511 				err = got_error_from_errno("asprintf");
512 				goto done;
513 			}
514 			err = got_pathlist_append(&have_refs, branchname, id);
515 			if (err) {
516 				free(branchname);
517 				goto done;
518 			}
519 		}
520 	}
521 
522 	if (list_refs_only) {
523 		packfd = got_opentempfd();
524 		if (packfd == -1) {
525 			err = got_error_from_errno("got_opentempfd");
526 			goto done;
527 		}
528 	} else {
529 		if (asprintf(&path, "%s/%s/fetching.pack",
530 		    repo_path, GOT_OBJECTS_PACK_DIR) == -1) {
531 			err = got_error_from_errno("asprintf");
532 			goto done;
533 		}
534 		err = got_opentemp_named_fd(&tmppackpath, &packfd, path);
535 		free(path);
536 		if (err)
537 			goto done;
538 	}
539 	if (list_refs_only) {
540 		idxfd = got_opentempfd();
541 		if (idxfd == -1) {
542 			err = got_error_from_errno("got_opentempfd");
543 			goto done;
544 		}
545 	} else {
546 		if (asprintf(&path, "%s/%s/fetching.idx",
547 		    repo_path, GOT_OBJECTS_PACK_DIR) == -1) {
548 			err = got_error_from_errno("asprintf");
549 			goto done;
550 		}
551 		err = got_opentemp_named_fd(&tmpidxpath, &idxfd, path);
552 		free(path);
553 		if (err)
554 			goto done;
555 	}
556 	nidxfd = dup(idxfd);
557 	if (nidxfd == -1) {
558 		err = got_error_from_errno("dup");
559 		goto done;
560 	}
561 
562 	for (i = 0; i < nitems(tmpfds); i++) {
563 		tmpfds[i] = got_opentempfd();
564 		if (tmpfds[i] == -1) {
565 			err = got_error_from_errno("got_opentempfd");
566 			goto done;
567 		}
568 	}
569 
570 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, imsg_fetchfds) == -1) {
571 		err = got_error_from_errno("socketpair");
572 		goto done;
573 	}
574 
575 	fetchpid = fork();
576 	if (fetchpid == -1) {
577 		err = got_error_from_errno("fork");
578 		goto done;
579 	} else if (fetchpid == 0){
580 		got_privsep_exec_child(imsg_fetchfds,
581 		    GOT_PATH_PROG_FETCH_PACK, tmppackpath);
582 	}
583 
584 	if (close(imsg_fetchfds[1]) != 0) {
585 		err = got_error_from_errno("close");
586 		goto done;
587 	}
588 	imsg_init(&fetchibuf, imsg_fetchfds[0]);
589 	nfetchfd = dup(fetchfd);
590 	if (nfetchfd == -1) {
591 		err = got_error_from_errno("dup");
592 		goto done;
593 	}
594 	err = got_privsep_send_fetch_req(&fetchibuf, nfetchfd, &have_refs,
595 	    fetch_all_branches, wanted_branches, wanted_refs,
596 	    list_refs_only, verbosity);
597 	if (err != NULL)
598 		goto done;
599 	nfetchfd = -1;
600 	npackfd = dup(packfd);
601 	if (npackfd == -1) {
602 		err = got_error_from_errno("dup");
603 		goto done;
604 	}
605 	err = got_privsep_send_fetch_outfd(&fetchibuf, npackfd);
606 	if (err != NULL)
607 		goto done;
608 	npackfd = -1;
609 
610 	packfile_size = 0;
611 	progress = calloc(GOT_FETCH_PKTMAX, 1);
612 	if (progress == NULL) {
613 		err = got_error_from_errno("calloc");
614 		goto done;
615 	}
616 
617 	*pack_hash = calloc(1, sizeof(**pack_hash));
618 	if (*pack_hash == NULL) {
619 		err = got_error_from_errno("calloc");
620 		goto done;
621 	}
622 
623 	while (!done) {
624 		struct got_object_id *id = NULL;
625 		char *refname = NULL;
626 		char *server_progress = NULL;
627 		off_t packfile_size_cur = 0;
628 
629 		err = got_privsep_recv_fetch_progress(&done,
630 		    &id, &refname, symrefs, &server_progress,
631 		    &packfile_size_cur, (*pack_hash)->sha1, &fetchibuf);
632 		if (err != NULL)
633 			goto done;
634 		if (!done && refname && id) {
635 			err = got_pathlist_insert(NULL, refs, refname, id);
636 			if (err)
637 				goto done;
638 		} else if (!done && server_progress) {
639 			char *p;
640 			/*
641 			 * XXX git-daemon tends to send batched output with
642 			 * lines spanning separate packets. Buffer progress
643 			 * output until we see a CR or LF to avoid giving
644 			 * partial lines of progress output to the callback.
645 			 */
646 			if (strlcat(progress, server_progress,
647 			    GOT_FETCH_PKTMAX) >= GOT_FETCH_PKTMAX) {
648 				progress[0] = '\0'; /* discard */
649 				continue;
650 			}
651 			while ((p = strchr(progress, '\r')) != NULL ||
652 			    (p = strchr(progress, '\n')) != NULL) {
653 				char *s;
654 				size_t n;
655 				char c = *p;
656 				*p = '\0';
657 				if (asprintf(&s, "%s%s", progress,
658 				    c == '\n' ? "\n" : "") == -1) {
659 					err = got_error_from_errno("asprintf");
660 					goto done;
661 				}
662 				err = progress_cb(progress_arg, s,
663 				    packfile_size_cur, 0, 0, 0, 0);
664 				free(s);
665 				if (err)
666 					break;
667 				n = strlen(progress);
668 				if (n < GOT_FETCH_PKTMAX - 1) {
669 					memmove(progress, &progress[n + 1],
670 					    GOT_FETCH_PKTMAX - n - 1);
671 				} else
672 					progress[0] = '\0';
673 			}
674 			free(server_progress);
675 			if (err)
676 				goto done;
677 		} else if (!done && packfile_size_cur != packfile_size) {
678 			err = progress_cb(progress_arg, NULL,
679 			    packfile_size_cur, 0, 0, 0, 0);
680 			if (err)
681 				break;
682 			packfile_size = packfile_size_cur;
683 		}
684 	}
685 	if (waitpid(fetchpid, &fetchstatus, 0) == -1) {
686 		err = got_error_from_errno("waitpid");
687 		goto done;
688 	}
689 
690 	if (lseek(packfd, 0, SEEK_SET) == -1) {
691 		err = got_error_from_errno("lseek");
692 		goto done;
693 	}
694 
695 	/* If zero data was fetched without error we are already up-to-date. */
696 	if (packfile_size == 0) {
697 		free(*pack_hash);
698 		*pack_hash = NULL;
699 		goto done;
700 	} else if (packfile_size < sizeof(pack_hdr) + SHA1_DIGEST_LENGTH) {
701 		err = got_error_msg(GOT_ERR_BAD_PACKFILE, "short pack file");
702 		goto done;
703 	} else {
704 		ssize_t n;
705 
706 		n = read(packfd, &pack_hdr, sizeof(pack_hdr));
707 		if (n == -1) {
708 			err = got_error_from_errno("read");
709 			goto done;
710 		}
711 		if (n != sizeof(pack_hdr)) {
712 			err = got_error(GOT_ERR_IO);
713 			goto done;
714 		}
715 		if (pack_hdr.signature != htobe32(GOT_PACKFILE_SIGNATURE)) {
716 			err = got_error_msg(GOT_ERR_BAD_PACKFILE,
717 			    "bad pack file signature");
718 			goto done;
719 		}
720 		if (pack_hdr.version != htobe32(GOT_PACKFILE_VERSION)) {
721 			err = got_error_msg(GOT_ERR_BAD_PACKFILE,
722 			    "bad pack file version");
723 			goto done;
724 		}
725 		nobj = betoh32(pack_hdr.nobjects);
726 		if (nobj == 0 &&
727 		    packfile_size > sizeof(pack_hdr) + SHA1_DIGEST_LENGTH)
728 			return got_error_msg(GOT_ERR_BAD_PACKFILE,
729 			    "bad pack file with zero objects");
730 		if (nobj != 0 &&
731 		    packfile_size <= sizeof(pack_hdr) + SHA1_DIGEST_LENGTH)
732 			return got_error_msg(GOT_ERR_BAD_PACKFILE,
733 			    "empty pack file with non-zero object count");
734 	}
735 
736 	/*
737 	 * If the pack file contains no objects, we may only need to update
738 	 * references in our repository. The caller will take care of that.
739 	 */
740 	if (nobj == 0)
741 		goto done;
742 
743 	if (lseek(packfd, 0, SEEK_SET) == -1) {
744 		err = got_error_from_errno("lseek");
745 		goto done;
746 	}
747 
748 	err = check_pack_hash(packfd, packfile_size, (*pack_hash)->sha1);
749 	if (err)
750 		goto done;
751 
752 	if (lseek(packfd, 0, SEEK_SET) == -1) {
753 		err = got_error_from_errno("lseek");
754 		goto done;
755 	}
756  
757 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, imsg_idxfds) == -1) {
758 		err = got_error_from_errno("socketpair");
759 		goto done;
760 	}
761 	idxpid = fork();
762 	if (idxpid == -1) {
763 		err= got_error_from_errno("fork");
764 		goto done;
765 	} else if (idxpid == 0)
766 		got_privsep_exec_child(imsg_idxfds,
767 		    GOT_PATH_PROG_INDEX_PACK, tmppackpath);
768 	if (close(imsg_idxfds[1]) != 0) {
769 		err = got_error_from_errno("close");
770 		goto done;
771 	}
772 	imsg_init(&idxibuf, imsg_idxfds[0]);
773 
774 	npackfd = dup(packfd);
775 	if (npackfd == -1) {
776 		err = got_error_from_errno("dup");
777 		goto done;
778 	}
779 	err = got_privsep_send_index_pack_req(&idxibuf, (*pack_hash)->sha1,
780 	    npackfd);
781 	if (err != NULL)
782 		goto done;
783 	npackfd = -1;
784 	err = got_privsep_send_index_pack_outfd(&idxibuf, nidxfd);
785 	if (err != NULL)
786 		goto done;
787 	nidxfd = -1;
788 	for (i = 0; i < nitems(tmpfds); i++) {
789 		err = got_privsep_send_tmpfd(&idxibuf, tmpfds[i]);
790 		if (err != NULL)
791 			goto done;
792 		tmpfds[i] = -1;
793 	}
794 	done = 0;
795 	while (!done) {
796 		int nobj_total, nobj_indexed, nobj_loose, nobj_resolved;
797 
798 		err = got_privsep_recv_index_progress(&done, &nobj_total,
799 		    &nobj_indexed, &nobj_loose, &nobj_resolved,
800 		    &idxibuf);
801 		if (err != NULL)
802 			goto done;
803 		if (nobj_indexed != 0) {
804 			err = progress_cb(progress_arg, NULL,
805 			    packfile_size, nobj_total,
806 			    nobj_indexed, nobj_loose, nobj_resolved);
807 			if (err)
808 				break;
809 		}
810 		imsg_clear(&idxibuf);
811 	}
812 	if (close(imsg_idxfds[0]) == -1) {
813 		err = got_error_from_errno("close");
814 		goto done;
815 	}
816 	if (waitpid(idxpid, &idxstatus, 0) == -1) {
817 		err = got_error_from_errno("waitpid");
818 		goto done;
819 	}
820 
821 	err = got_object_id_str(&id_str, *pack_hash);
822 	if (err)
823 		goto done;
824 	if (asprintf(&packpath, "%s/%s/pack-%s.pack",
825 	    repo_path, GOT_OBJECTS_PACK_DIR, id_str) == -1) {
826 		err = got_error_from_errno("asprintf");
827 		goto done;
828 	}
829 
830 	if (asprintf(&idxpath, "%s/%s/pack-%s.idx",
831 	    repo_path, GOT_OBJECTS_PACK_DIR, id_str) == -1) {
832 		err = got_error_from_errno("asprintf");
833 		goto done;
834 	}
835 
836 	if (rename(tmppackpath, packpath) == -1) {
837 		err = got_error_from_errno3("rename", tmppackpath, packpath);
838 		goto done;
839 	}
840 	free(tmppackpath);
841 	tmppackpath = NULL;
842 	if (rename(tmpidxpath, idxpath) == -1) {
843 		err = got_error_from_errno3("rename", tmpidxpath, idxpath);
844 		goto done;
845 	}
846 	free(tmpidxpath);
847 	tmpidxpath = NULL;
848 
849 done:
850 	if (tmppackpath && unlink(tmppackpath) == -1 && err == NULL)
851 		err = got_error_from_errno2("unlink", tmppackpath);
852 	if (tmpidxpath && unlink(tmpidxpath) == -1 && err == NULL)
853 		err = got_error_from_errno2("unlink", tmpidxpath);
854 	if (nfetchfd != -1 && close(nfetchfd) == -1 && err == NULL)
855 		err = got_error_from_errno("close");
856 	if (npackfd != -1 && close(npackfd) == -1 && err == NULL)
857 		err = got_error_from_errno("close");
858 	if (packfd != -1 && close(packfd) == -1 && err == NULL)
859 		err = got_error_from_errno("close");
860 	if (idxfd != -1 && close(idxfd) == -1 && err == NULL)
861 		err = got_error_from_errno("close");
862 	for (i = 0; i < nitems(tmpfds); i++) {
863 		if (tmpfds[i] != -1 && close(tmpfds[i]) == -1 && err == NULL)
864 			err = got_error_from_errno("close");
865 	}
866 	free(tmppackpath);
867 	free(tmpidxpath);
868 	free(idxpath);
869 	free(packpath);
870 	free(ref_prefix);
871 	free(progress);
872 
873 	TAILQ_FOREACH(pe, &have_refs, entry) {
874 		free((char *)pe->path);
875 		free(pe->data);
876 	}
877 	got_pathlist_free(&have_refs);
878 	got_ref_list_free(&my_refs);
879 	if (err) {
880 		free(*pack_hash);
881 		*pack_hash = NULL;
882 		TAILQ_FOREACH(pe, refs, entry) {
883 			free((void *)pe->path);
884 			free(pe->data);
885 		}
886 		got_pathlist_free(refs);
887 		TAILQ_FOREACH(pe, symrefs, entry) {
888 			free((void *)pe->path);
889 			free(pe->data);
890 		}
891 		got_pathlist_free(symrefs);
892 	}
893 	return err;
894 }